In his analysis of the concept of causality, Hume finds that all events accounted causes and effects are contiguous and successive. No object can act efficaciously upon another so long as the objects are at a distance from each other. It may sometimes appear that “distant objects are productive of one another,” but on examination it is discovered that they are linked together by a series of intermediate causes which are contiguous among themselves; and even where examination does not directly disclose the intermediate causal chain, it is still presumed that it exists. Also the cause is temporally prior to the effect. If I throw a stone through a window, the smashing of the glass follows the act of throwing the stone. It is only after the realization of the cause that the effect appears. Thus a cause is an object that is precedent to and contiguous with another object that is called the effect.

There are, plainly, very many reasons why a controversy should be inconclusive and abortive, and yet constantly reviving. It might, for example, be one that interests only the very stupid or prejudiced; or one that interests everyone deeply, demanding an answer of everyone, yet not yielding any really decisive evidence; or the controversy might be one in which thesis and antithesis are natural expressions of opposed psychological types (“Tough-” and “Tender-minded” people); or it might be one that is commonly conducted in terms that are vague, misleading, and question-begging. In this paper I shall confine myself to the last of these reasons: the use of language which makes it extremely difficult to understand what either of the parties are really asserting, and where, if at all, they contradict each other. I hope I shall not be thought to exaggerate the importance of this familiar factor, but I hope to show that in many important controversies the best will in the world and all the patience and tolerance a man can muster are not sufficient: special training and considerable independent reflection are necessary if the debate in question is not to prove as profitless as those described by Omar Khayyam of Naishapur:

Myself when young did eagerly frequent

Doctor and Saint, and heard great Argument

About it and about: but evermore

Came out by the same Door as in I went.